CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims the benefit of priority from the prior
Japanese Patent Application No. P2001-224867, filed on July 25, 2001; the entire contents
of which are incorporated herein by reference.
BACKGRAOUND OF THE INVENTION
Field of the Invention
[0002] This invention relates to a mobile packet communications system, a mobile packet
communications method, and a radio network controller that are adapted to provide
a packet communications service to mobile stations.
Description of the Relevant Art
[0003] A typical mobile packet communications system employs, in view of the efficiency
in use of frequency as well as a permissible delay in the packet communications, a
method of time-multiplexing data of a plurality of users in a single radio channel.
In this mobile packet communications system, which has as equipment to its radio base
station or radio network controller a user data buffer provided every user for temporary
storage of data of the user, the limit in amount of data that can be stored in the
user data buffer does constitute a hardware-dependent limitation to the number of
concurrently connectable users, that is, the number of concurrently settable packet
calls (calls for packet communications).
[0004] In the typical mobile packet communications system, however, the user data buffer
has a sufficient region secured for data storage thereto, which could admit packet
calls as setup-requested from users until the user data buffer fills up. In such situation,
it is regarded as a problem that increased transmission delay causing a degraded quality
occurs.
[0005] For solution of this problem, in a known mobile packet communications system, the
setup of packet call setup-requested from user is controlled not for admission up
to a limit of hardware, but for admission in dependence on the condition of use of
down-link transmission power.
[0006] An entire configuration of the mobile packet communications system is shown in Fig.
1. This mobile packet communications system is configured, as shown in Fig. 1, with
mobile stations 10, radio base stations 20, radio network controllers 30, and an exchanger
40.
[0007] Each mobile station 10, connected by a radio connection to a radio base station 20,
is configured with a radio communications terminal, such as a portable telephone terminal
(with an IMT-2000 conforming portable telephone terminal inclusive), or a portable
information terminal (PDA).
[0008] Each radio base station 20, connected by radio connections to mobile stations 10,
is connected by a wired connection or radio connection to a radio network controller
30. Radio base station 20 is controlled by radio network controller 30, for radio
communications with mobile stations 10 residing within a cell region under own control.
[0009] Each radio network controller 30 is connected to the exchanger 40 and to radio base
stations 20, and controls the radio base stations 20 to control radio communications
of mobile stations 10. Radio network controller 30 receives a "call admission request
(setup request of packet call)" from a mobile station 10, as it is transmitted via
a radio base station 20, and performs a decision of whether or not to admit packet
call for the admission request, and upon a decision for admission of packet call,
transfers to the exchanger 40 a request for the setup of packet call.
[0010] Fig. 2 diagrams simply part of configuration of radio network controller 30 associated
with the above-noted control in the mobile packet communications system described.
As shown in Fig. 2, radio network controller 30 is configured with a call processor
31, a call admission controller 32, and a memory 33.
[0011] The call processor 31, connected to the call admission controller 32, receives a
call admission request from mobile station 10 and transfers the same to the call admission
controller 32. Further, the call processor 31 answers the mobile station 10 of a result
of a decision transmitted from the call admission controller 32 as to whether or not
to admit packet call for the above-noted call admission request.
[0012] The call admission controller 32, connected to the call processor 31, decides whether
or not to admit packet call for the call admission request transferred from the call
processor 31, and transmits a result of the decision to the call processor 31. The
call processor 31 is periodically reported from radio base station 20 of "down-link
transmission power P" in current use at the radio base station 20. The call admission
controller 32, holding a "prescribed threshold T", performs a decision of whether
or not to admit packet call for the call admission request transferred from the call
processor 31, depending on a result of comparison of the "down-link transmission power
P" and the "prescribed threshold T".
[0013] The memory 33, connected to the call admission controller 32, stores therein information
on currently set packet calls. The information encompasses, as shown in Fig. 2 for
example, a "call ID" that is information for discrimination of a currently connected
packet call, a "release timer" that indicates a residual time up to a release of the
packet call, a "connected number of calls" that indicates the number of currently
connected packet calls, etc.
[0014] The exchanger 40, connected to radio network controller 30, performs an exchange
process relative to a setup request of packet call transferred from the radio network
controller 30. The exchanger 40 is connected via a trunk network 100 to other exchangers.
[0015] Fig. 3 shows actions to be taken when a call admission request is transmitted from
a mobile station 10 in the mobile packet communications system described.
[0016] As shown in Fig. 3, at a step S802, the call processor 31 of a radio network controller
30 receives a call admission request transmitted from the mobile station 10 via a
radio base station 20. At a step S804, the call admission controller 32 of the radio
network controller 30 receives the call admission request transferred from the call
processor 31.
[0017] At a step S806, the call admission controller 32 compares a magnitude of "down-link
transmission power P", which is periodically reported from the radio base station
20 as in current use at the radio base station 20, with a "prescribed threshold T"
under own control.
[0018] If the "down-link transmission power P" is smaller than the "prescribed threshold
T", the flow of control goes to a step S808, where the call admission controller 32
transmits to the call processor 31 a "call admission permission notice" notifying
an admission of packet call to be effected for the above-noted call admission request,
and stores in the memory 33 information on a call associated with the call admission
request.
[0019] Unless the "down-link transmission power P" is smaller than the "prescribed threshold
T", the flow goes to a step S810, where the call admission controller 32 transmits
to the call processor 31 a "call admission rejection notice" notifying no admission
of packet call to be effected for the above-noted call admission request. The call
processor 31 is responsible for the "call admission permission notice" or "call admission
rejection notice" transmitted from the call admission controller 32 to execute a necessary
process relative to the call admission request from the mobile station 10.
[0020] In the mobile packet communications system described, however, a controller for setting
a circuit-switching-oriented call (voice call) is applied to the setup of packet call
as well, with an occasional failure to exhibit an expected effect.
[0021] For example, for a radio base station 20 that has many mobile stations 10 performing
radio communications in places relatively vicinal thereto and can do with a small
amount of down-link transmission power P to be used there, the call admission controller
32 of an associated radio network controller 30 may admit setup admission of an excessive
number of packet calls, with the result that an increased transmission delay causes
a degraded quality, as a problem under the above-noted condition in the mobile packet
communications system described.
[0022] In the case of a radio base station 20 has many mobile stations 10 performing radio
communications in places relatively distant therefrom, the above-noted problem does
not occur due to control depending on the down-link transmission power P. In such
situation, however, a single radio channel may undergo a time division to be commonly
employed by a plurality of users, leading to a failure to well utilize such an advantage
of mobile packet communications that users are allowed to perform radio communications
unless their data have temporal overlaps even when a great magnitude of down-link
transmission power P is used at the radio base station 20. As a result, a problem
that a reduced throughput over an entirety of the mobile packet communications system
occurs.
BRIEF SUMMARY OF THE INVENTION
[0023] It is an object of this invention to provide a mobile packet communications system,
allowing for utilization of the above-noted advantage of mobile packet communications
to have an improved efficiency in use of radio channel resources, while limiting increase
in transmission delay to prevent degradation of quality.
[0024] According to a first aspect of this invention, a mobile packet communications system
comprises a memory configured to store information on currently set packet calls,
a new call decider implemented, upon reception of a setup request of a packet call
transmitted from a mobile station, to make a decision depending on the information
stored in the memory, as to whether or not the packet call setup-requested is a new
call, and an admission concluder implemented, upon a decision for the packet call
to be the new call, to conclude whether or not to admit the packet call.
[0025] A mobile packet communications system according to the first aspect of this invention
may preferably have the memory configured to store a number of the currently set packet
calls, and the admission concluder implemented to sample the number of the currently
set packet calls, and to give a conclusion as to whether or not to admit the packet
call depending on the sampled number of the currently set packet calls.
[0026] A mobile packet communications system of a W-CDMA system configured with a mobile
packet communications system according to the first aspect of this invention may preferably
have the memory configured to store a number of currently set A-DPCH's, and the admission
concluder implemented to sample the number of the currently set A-DPCH's, and to give
a conclusion as to whether or not to admit the packet call depending on the sampled
number of the currently set A-DPCH's.
[0027] A mobile packet communications system according to the first aspect of this invention
may preferably comprise a buffer configured to store data addressed and transmitted
to the currently set packet calls, and a queue processor implemented to transfer onto
the packet call the data stored in the buffer, measuring an amount of data transferred
onto the packet call per unit time, and have the admission concluder implemented to
give a conclusion as to whether or not to admit the packet call depending on the amount
of data measured at the queue processor.
[0028] A mobile packet communications system according to the first aspect of this invention
may preferably comprise a buffer configured to store data addressed and transmitted
to the currently set packet calls, a queue processor implemented to transfer onto
the packet call the data stored in the buffer, a delay time calculator implemented
to calculate a delay time depending on a time when the data is stored in the buffer
and a time when the data is transferred onto the packet call by the queue processor,
and a delay time averager implemented to determine an average within a prescribed
interval with respect to the delay time calculated by the delay time calculator, and
have the admission concluder is implemented to give a conclusion as to whether or
not to admit the packet call depending on the average determined by the delay time
averager.
[0029] According to a second aspect of this invention, a mobile packet communications method
comprises the steps of making, upon reception of a setup request of a packet call
transmitted from a mobile station, a decision depending on information on currently
set packet calls stored in a memory, as to whether or not the packet call setup-requested
is a new call, and concluding, upon a decision for the packet call to be the new call,
whether or not to admit the packet call.
[0030] A mobile packet communications method according to the second aspect of this invention
may preferably have the concluding comprising sampling a number of the currently set
packet calls from the memory, and giving a conclusion as to whether or not to admit
the packet call depending on the sampled number of the currently set packet calls.
[0031] A mobile packet communications method of a W-CDMA system implemented with a mobile
packet communications method according to the second aspect of this invention may
preferably have the concluding comprising sampling a number of currently set A-DPCH's
from the memory, and giving a conclusion as to whether or not to admit the packet
call depending on the sampled number of the currently set A-DPCH's.
[0032] A mobile packet communications method according to the second aspect of this invention
may preferably comprise the steps of storing in a buffer data addressed and transmitted
to the currently set packet calls, and transferring onto the packet call the data
stored in the buffer, measuring an amount of data transferred onto the packet call
per unit time, and have the concluding comprising giving a conclusion as to whether
or not to admit the packet call depending on the measured amount of data.
[0033] A mobile packet communications method according to the second aspect of this invention
may preferably comprise the steps of storing in a buffer data addressed and transmitted
to the currently set packet calls, transferring onto the packet call the data stored
in the buffer, calculating a delay time depending on a time when the data is stored
in the buffer and a time when the data is transferred onto the packet call, and determining
an average within a prescribed interval with respect to the calculated delay time,
and have the concluding comprising giving a conclusion as to whether or not to admit
the packet call depending on the determined average.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0034]
Fig. 1 is a diagram of a mobile packet communications system according to an embodiment
of the invention.
Fig. 2 is a functional block diagram of a radio network controller of a mobile packet
communications system according to conventional art.
Fig. 3 is a flow chart of actions of the mobile packet communications system according
to conventional art.
Fig. 4 is a functional block diagram of a radio network controller of a mobile packet
communications system according to an embodiment of the invention.
Fig. 5 is a flow chart of actions of a mobile packet communications system according
to an embodiment of the invention.
Fig. 6 is a flow chart of actions of a mobile packet communications system according
to an embodiment of the invention.
Fig. 7 is a flow chart of actions of a mobile packet communications system according
to an embodiment of the invention.
Fig. 8 is a flow chart of actions of a mobile packet communications system according
to an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0035] (Configuration of a mobile packet communications system according to an embodiment)
[0036] There will be detailed below embodiments of the invention with reference to the drawings.
Fig. 1 shows an example of an entire configuration of a mobile packet communications
system according to this embodiment of the invention, as a diagram simply taken of
part associated with the invention.
[0037] The entire configuration of the mobile packet communications system according to
the embodiment is analogous to that of the conventional mobile packet communications
system described. The mobile packet communications system according to the embodiment
includes mobile stations 10, radio network controllers 30, and an exchanger 40 analogous
to those employed in the conventional mobile packet communications system.
[0038] In the mobile packet communications system according to the embodiment, radio network
controller 30 is configured, like the conventional mobile packet communications system,
for connections to the exchanger 40 and to radio base stations 20, and for controlling
the radio base stations 20 to control radio communications of mobile stations 10.
Further, in the mobile packet communications system according to the embodiment, radio
network controller 30 is configured to receive a "call admission request (setup request
of packet call)" from a mobile station 10, as it is transmitted via a radio base station
20, and to make a decision of whether or not to admit packet call for the admission
request, and upon a decision for admission of packet call, to transfer to the exchanger
40 a request for the setup of packet call.
[0039] Fig. 1 shows an example of configuration of a radio network controller 30 of the
mobile packet communications system according to the embodiment, as a diagram simply
taken of part the radio network controller 30 associated with the invention. In the
mobile packet communications system according to the embodiment, as shown in Fig.
4, radio network controller 30 is configured with a call processor 31, a call admission
controller 32, a memory 33, a user data buffer 34, a queue processor 35, and a delay
time storing averager 36..
[0040] The call processor 31, connected to the call admission controller 32 and the user
data buffer 34, is implemented to receive a call admission request from mobile station
10 and transfer the received call admission request to the call admission controller
32. The call processor 31 is further implemented to answer the mobile station 10 of
a result of a decision transmitted from the call admission controller 32 as to whether
or not to admit packet call for the above-noted call admission request.
[0041] The call processor 31 is implemented, as the setup of packet call is admitted (with
a packet call connected relative to the mobile station 10), to order the user data
buffer 34 to have a region set for the admitted packet call (i.e. the mobile station
10), and when the connection of packet call is released, to order the user data buffer
34 to release a region that has been dedicated as the region for the packet call (mobile
station 10).
[0042] In application of the mobile packet communications system according to the embodiment
to a mobile packet communications network of a W-CDMA system, the call processor 31
is implemented to transmit to the radio bases station 20 a setup or release order
of an A-DPCH (associated dedicated physical channel) in accordance with an instruction
from the call admission controller 32.
[0043] The call admission controller 32, connected to the call processor 31, the memory
33, the user data buffer 34, the queue processor 35, and the delay tme storing averager
36, is configured as a new call decider implemented, upon reception of a "call admission
request (a setup request of a packet call)" transmitted from a mobile station 10,
to make a decision depending on whether or not it is stored in the memory 33 as a
currently set packet call, as to whether or not the packet call associated with the
above-noted call admission request is a "new call (that is a packet call not currently
set)".
[0044] The call admission controller 32 is further configured as an admission concluder
implemented to give a conclusion as to whether or not to admit the packet call associated
with the call admission request transferred from the call processor 31, and to transmit
a result of the conclusion to the call processor 31.
[0045] The call admission controller 32 is implemented to release the connection of a packet
call of which a "release timer" stored in the memory 33 is time out (that is, a value
of the "release timer" has become "0"), updating information on the packet call in
the memory 33.
[0046] In application of the mobile packet communications system according to the embodiment
to a mobile packet communications network of a W-CDMA system, the call admission controller
32 is implemented to control setup and release of an A-DPCH, updating information
on the number of connections of A-DPCH's in the memory 33 in accordance with the setup
and release of the A-DPCH.
[0047] The memory 33, connected to the call admission controller 32, is configured to serve
as a memory for storing therein information on currently set packet calls. The information
encompasses, as shown in Fig. 4 for example, a "call ID" that is information for discrimination
of a currently connected packet call, the "release timer" that indicates a residual
time up to a release of the packet call, a "connected number of calls" that indicates
the number of currently connected packet calls, etc.
[0048] In application of the mobile packet communications system according to the embodiment
to a mobile packet communications network of a W-CDMA system, the memory 33 is implemented
to store the number of connections of current A-DPCH's.
[0049] The user data buffer 34, connected to the call processor 31, the queue processor
35, and the delay time storing averager 36, is configured to have a region secured
every currently set packet call (mobile station 10 with a packet call set therefor),
serving as a buffer to store, for a temporary interval of time before transmission
to a radio base station 20, a data (packet) addressed and transmitted, every set packet
call (mobile station 10), from the exchanger 40 to the packet call. In this embodiment,
as shown in Fig. 4, the user data buffer 34 is configured with a total of n user data
buffers #1 to #n for adaptation to have secured regions for n mobile stations 10.
[0050] The user data buffer 34 is implemented to store the time when a transmitted data
from exchanger 40 to packet call (mobile station 10) is stored and the time when the
data is transferred to the radio base station 20 (or the time when the data is read
by the queue processor 35), and to transmit a difference therebetween as a delay time
to the delay time storing averager 36. The region to be secured and released at the
user data buffer 34 is controlled by an order transmitted from the call processor
31 in accordance with an instruction from the call admission controller 32.
[0051] The queue processor 35, connected to the call admission controller 32, the user data
buffer 34, and the delay time storing averager 36, is configured as a queue processor
for reading, every set packet call (mobile station 10), the data stored in the user
data buffer 34, transferring the read data to the radio base station 20 on the packet
call.
[0052] The queue processor 35 is implemented to count (measure) the amount of data transmitted
to the radio base station 20 per unit time, periodically transmitting a result of
the count to the call admission controller 32. The result of count is assumed as a
throughput of the mobile packet communications system according to the embodiment.
[0053] The delay time storing averager 36, connected to the call admission controller 32
and the user data buffer 34, is configured as a delay time storing averager for determining
an average within a prescribed interval with respect to the delay time transmitted
from the user data buffer 34, to transmit an average of delay time thus determined
to the call admission controller 32.
(Actions of mobile packet communications system according to the embodiment)
[0054] As actions of a mobile packet communications system according to the embodiment,
there are four methods shown in Fig. 5 to Fig. 8. Fig. 5 to Fig. 8 are diagrammatic
flowcharts showing sequences to be followed upon reception of a call admission request
from a mobile station 10 in the mobile packet communications system according to the
embodiment, as examples taken simply in part associated with the invention.
(First sequence)
[0055] As shown in Fig. 5, at a step S302, the call processor 31 of a radio network controller
30 receives a call admission request transmitted from a mobile station 10 via a radio
base station 20. At a step S304, the call admission controller 32 of the radio network
controller 30 receives the call admission request transferred from the call processor
31.
[0056] At a step S306, the call admission controller 32 retrieves whether or not a packet
call associated with the above-noted call admission request is stored as a currently
set packet call in the memory 33.
[0057] If the packet call associated with the call admission request is stored as a currently
set packet call in the memory 33, the call admission controller 32 recognizes the
packet call as an "existing call (i.e., currently set packet call)", and the flow
of control goes to a step S316, where a "release timer" associated with the packet
call in the memory 33 is set (reset) to a maximum. Then, the action of mobile packet
communications system according to this embodiment goes to an end.
[0058] Unless the packet call associated with the call admission request is stored as a
currently set packet call in the memory 33, the call admission controller 32 recognizes
the packet call as a "new call (i.e., packet call not currently set)", and the flow
of control goes to a step S308.
[0059] At the step S308, the call admission controller 32 samples from the memory 33 a "connected
number of calls UN" that indicates the number of currently set packet calls. Then,
at a step S310, the call admission controller 32 compares the sampled "connected number
of calls UN" with a "prescribed threshold UA" under own control, where the "prescribed
threshold UA" is a prescribed upper limit in number of concurrently settable packet
calls.
[0060] If the "connected number of calls UN" is smaller than the "prescribed threshold UA",
the flow goes to a step S312, where the call admission controller 32 gives a conclusion
to admit the packet call associated with the above-noted call admission request, and
transmits to the call processor 31 a "call admission permission notice" as a notice
of the effect, storing in the memory 33 information on the packet call associated
with the call admission request, updating the content of storage in the memory 33.
[0061] Unless the "connected number of calls UN" is smaller than the "prescribed threshold
UA", the flow goes to a step S314, where the call admission controller 32 gives a
conclusion not to admit the packet call associated with the above-noted call admission
request, and transmits to the call processor 31 a "call admission rejection notice"
as a notice of the effect. The call processor 31 is responsible for the "call admission
permission notice" or "call admission rejection notice" transmitted from the call
admission controller 32 to execute a necessary process relative to the call admission
request from the mobile station 10.
(Second sequence)
[0062] The second sequence is for a mobile packet communications system according to this
embodiment, as it is applied to a mobile packet communications network using a W-CDMA
system. For this sequence, it is assumed that the number of set packet calls (mobile
stations 10) in the mobile packet communications network of W-CDMA system is substantially
equivalent to the number of DPCH's (A-DPCH's) accompanying radio channels for the
packet calls (mobile stations 10).
[0063] As shown in Fig. 6, at a step S402, the call processor 31 of a radio network controller
30 receives a call admission request transmitted from a mobile station 10 via a radio
base station 20. At a step S404, the call admission controller 32 of the radio network
controller 30 receives the call admission request transferred from the call processor
31.
[0064] At a step S406, the call admission controller 32 retrieves whether or not a packet
call associated with the above-noted call admission request is stored as a currently
set packet call in the memory 33.
[0065] If the packet call associated with the call admission request is stored as a currently
set packet call in the memory 33, the call admission controller 32 recognizes the
packet call as an "existing call (i.e., currently set packet call)", and the flow
of control goes to a step S416, where a "release timer" associated with the packet
call in the memory 33 is set (reset) to a maximum. Then, the action of mobile packet
communications system according to this embodiment goes to an end.
[0066] Unless the packet call associated with the call admission request is stored as a
currently set packet call in the memory 33, the call admission controller 32 recognizes
the packet call as a "new call (i.e., packet call not currently set)", and the flow
of control goes to a step S408.
[0067] At the step S408, the call admission controller 32 samples from the memory 33 an
"A-DPCH concurrent number of connections N
A-DPCH" that indicates the number of currently set A-DPCH's. Then, at a step S410, the call
admission controller 32 compares the sampled "A-DPCH concurrent number of connections
N
A-DPCH" with a "prescribed threshold M
A-DPCH" under own control, where the "prescribed threshold M
A-DPCH" is a prescribed upper limit in number of concurrently settable A-DPCH's.
[0068] If the "A-DPCH concurrent number of connections N
A-DPCH" is smaller than the "prescribed threshold M
A-DPCH", the flow goes to a step S412, where the call admission controller 32 gives a conclusion
to admit the packet call associated with the above-noted call admission request, and
transmits to the call processor 31 a "call admission permission notice" as a notice
of the effect, storing in the memory 33 information on the packet call associated
with the call admission request, updating the content of storage in the memory 33.
[0069] Unless the "A-DPCH concurrent number of connections N
A-DPCH" is smaller than the "prescribed threshold M
A-DPCH", the flow goes to a step S414, where the call admission controller 32 gives a conclusion
not to admit the packet call associated with the above-noted call admission request,
and transmits to the call processor 31 a "call admission rejection notice" as a notice
of the effect. The call processor 31 is responsible for the "call admission permission
notice" or "call admission rejection notice" transmitted from the call admission controller
32 to execute a necessary process relative to the call admission request from the
mobile station 10.
(Third sequence)
[0070] As shown in Fig. 7, at a step S502, the call processor 31 of a radio network controller
30 receives a call admission request transmitted from a mobile station 10 via a radio
base station 20. At a step S504, the call admission controller 32 of the radio network
controller 30 receives the call admission request transferred from the call processor
31.
[0071] At a step S506, the call admission controller 32 retrieves whether or not a packet
call associated with the above-noted call admission request is stored as a currently
set packet call in the memory 33.
[0072] If the packet call associated with the call admission request is stored as a currently
set packet call in the memory 33, the call admission controller 32 recognizes the
packet call as an "existing call (i.e., currently set packet call)", and the flow
of control goes to a step S516, where a "release timer" associated with the packet
call in the memory 33 is set (reset) to a maximum. Then, the action of mobile packet
communications system according to this embodiment goes to an end.
[0073] Unless the packet call associated with the call admission request is stored as a
currently set packet call in the memory 33, the call admission controller 32 recognizes
the packet call as a "new call (i.e., packet call not currently set)", and the flow
of control goes to a step S508.
[0074] At the step S508, the call admission controller 32 determines a "current system throughput
TN" based on a result of count periodically transmitted from the queue processor 35.
Then, at a step S510, the call admission controller 32 compares the determined "current
system throughput TN" with a "prescribed threshold TA" under own control, where the
"prescribed threshold TA" is a prescribed upper limit of throughput per unit time.
[0075] If the "current system throughput TN" is smaller than the "prescribed threshold TA",
the flow goes to a step S512, where the call admission controller 32 gives a conclusion
to admit the packet call associated with the above-noted call admission request, and
transmits to the call processor 31 a "call admission permission notice" as a notice
of the effect, storing in the memory 33 information on the packet call associated
with the call admission request, updating the content of storage in the memory 33.
[0076] Unless the "current system throughput TN" is smaller than the "prescribed threshold
TA", the flow goes to a step S514, where the call admission controller 32 gives a
conclusion not to admit the packet call associated with the above-noted call admission
request, and transmits to the call processor 31 a "call admission rejection notice"
as a notice of the effect. The call processor 31 is responsible for the "call admission
permission notice" or "call admission rejection notice" transmitted from the call
admission controller 32 to execute a necessary process relative to the call admission
request from the mobile station 10.
(Fourth sequence)
[0077] As shown in Fig. 8, at a step S602, the call processor 31 of a radio network controller
30 receives a call admission request transmitted from a mobile station 10 via a radio
base station 20. At a step S604, the call admission controller 32 of the radio network
controller 30 receives the call admission request transferred from the call processor
31.
[0078] At a step S606, the call admission controller 32 retrieves whether or not a packet
call associated with the above-noted call admission request is stored as a currently
set packet call in the memory 33.
[0079] If the packet call associated with the call admission request is stored as a currently
set packet call in the memory 33, the call admission controller 32 recognizes the
packet call as an "existing call (i.e., currently set packet call)", and the flow
of control goes to a step S616, where a "release timer" associated with the packet
call in the memory 33 is set (reset) to a maximum. Then, the action of mobile packet
communications system according to this embodiment goes to an end.
[0080] Unless the packet call associated with the call admission request is stored as a
currently set packet call in the memory 33, the call admission controller 32 recognizes
the packet call as a "new call (i.e., packet call not currently set)", and the flow
of control goes to a step S608.
[0081] At the step S608, the call admission controller 32 determines a "current average
delay time TD" based on the delay time transmitted from the delay time storing averager
36. Then, at a step S610, the call admission controller 32 compares the determined
"current average delay time TD" with a "prescribed threshold AD" under own control,
where the "prescribed threshold TD" is a prescribed upper limit of permissible delay
time.
[0082] If the "current average delay time TD" is smaller than the "prescribed threshold
AD", the flow goes to a step S612, where the call admission controller 32 gives a
conclusion to admit the packet call associated with the above-noted call admission
request, and transmits to the call processor 31 a "call admission permission notice"
as a notice of the effect, storing in the memory 33 information on the packet call
associated with the call admission request, updating the content of storage in the
memory 33.
[0083] Unless the "current average delay time TD" is smaller than the "prescribed threshold
AD", the flow goes to a step S614, where the call admission controller 32 gives a
conclusion not to admit the packet call associated with the above-noted call admission
request, and transmits to the call processor 31 a "call admission rejection notice"
as a notice of the effect. The call processor 31 is responsible for the "call admission
permission notice" or "call admission rejection notice" transmitted from the call
admission controller 32 to execute a necessary process relative to the call admission
request from the mobile station 10.
(Other embodiments)
[0084] The foregoing embodiments may also be modified in various manners within the scope
of appended claims, as the modifications fall within a scope of technical concept
recited in the claims.
(Effects and functions of mobile packet communications systems according to the embodiment)
[0085] According to the embodiment described, in a mobile packet communications system,
a call admission controller 32 is adapted to make a decision depending on information
stored in a memory 33, as to whether or not a setup-requested packet call is a new
call, and to give a conclusion as to whether or not to admit the packet call, simply
in respect of new calls excepting existing calls.
[0086] According to the embodiment described, in a mobile packet communications system,
a call admission controller 32 is adapted to give a conclusion depending on a "connected
number of calls UN" as the number of currently set packet calls, as to whether or
not to admit the packet call, thus overcoming the problem that an excessive number
of packet calls might otherwise have been admitted even when many mobile stations
10 perform radio communications in places relatively vicinal to a radio base station
20.
[0087] According to the embodiment described, in a mobile packet communications system,
a call admission controller 32 is adapted to give a conclusion depending on a "connected
number of calls UN" as the number of currently set packet calls, as to whether or
not to admit the packet call, thus allowing for utilization of an advantage of mobile
packet communications that users are allowed to perform radio communications unless
their data have temporal overlaps even when many mobile stations 10 perform radio
communications in places relatively distant from a radio base station 20, overcoming
the problem that the throughput of an entirety of the mobile packet communications
system might otherwise have been reduced.
[0088] According to the embodiment described, in a mobile packet communications system,
a call admission controller 32 is adapted to give a conclusion depending on an "A-DPCH
concurrent number of connections N
A-DPCH" as the number of currently set A-DPCH's to be substantially equivalent to the number
of currently set packet calls, as to whether or not to admit the packet call, thus
overcoming the problem that an excessive number of packet calls might otherwise have
been admitted even when many mobile stations 10 perform radio communications in places
relatively vicinal to a radio base station 20.
[0089] According to the embodiment described, in a mobile packet communications system,
a call admission controller 32 is adapted to give a conclusion depending on an "A-DPCH
concurrent number of connections N
A-DPCH" as the number of currently set A-DPCH's to be substantially equivalent to the number
of currently set packet calls, as to whether or not to admit the packet call, thus
allowing for utilization of an advantage of mobile packet communications that users
are allowed to perform radio communications unless their data have temporal overlaps
even when many mobile stations 10 perform radio communications in places relatively
distant from a radio base station 20, overcoming the problem that the throughput of
an entirety of the mobile packet communications system might otherwise have been reduced.
[0090] According to the embodiment described, in a mobile packet communications system,
a call admission controller 32 is adapted to give a conclusion depending on a "current
system throughput TN" as the amount of data measured by a queue processor 35, as to
whether or not to admit the packet call, thus preventing occurrences of an increased
delay time due to reduced throughput even when many mobile stations 10 perform radio
communications in places relatively vicinal to a radio base station 20.
[0091] According to the embodiment described, in a mobile packet communications system,
a call admission controller 32 is adapted to give a conclusion depending on a "current
average delay time TD" as an average within a prescribed interval with respect to
a delay time calculated by combination of a user data buffer 34 and a delay time storing
averager 36, as to whether or not to admit the packet call, thus preventing increase
in delay time even when many mobile stations 10 perform radio communications in places
relatively vicinal to a radio base station 20.
[0092] As will be seen from the foregoing description, according to the invention, there
can be provided a mobile packet communications system, allowing for utilization of
advantage of mobile packet communications to have an improved efficiency in use of
radio channel resources, while limiting increase in transmission delay to prevent
degradation of quality.
[0093] While preferred embodiments of the present invention have been described using specific
terms, such description is not given in any restrictive sense, but for illustrative
purposes, and it is to be understood that changes and variations may be made without
departing from the spirit or scope of the following claims.
1. A mobile packet communications system comprising:
a memory configured to store information on currently set packet calls;
a new call decider implemented, upon reception of a setup request of a packet call
transmitted from a mobile station, to make a decision depending on the information
stored in the memory, as to whether or not the packet call setup-requested is a new
call; and
an admission concluder implemented, upon a decision for the packet call to be the
new call, to conclude whether or not to admit the packet call.
2. A mobile packet communications system according to claim 1, wherein
the memory is configured to store a number of the currently set packet calls, and
the admission concluder is implemented to sample the number of the currently set
packet calls, and to give a conclusion as to whether or not to admit the packet call
depending on the sampled number of the currently set packet calls.
3. A mobile packet communications system of a W-CDMA system configured with a mobile
packet communications system according to claim 1, wherein
the memory is configured to store a number of currently set A-DPCH's, and
the admission concluder is implemented to sample the number of the currently set
A-DPCH's, and to give a conclusion as to whether or not to admit the packet call depending
on the sampled number of the currently set A-DPCH's.
4. A mobile packet communications system according to claim 1, comprising:
a buffer configured to store data addressed and transmitted to the currently set packet
calls; and
a queue processor implemented to transfer onto the packet call the data stored in
the buffer, measuring an amount of data transferred onto the packet call per unit
time, wherein
the admission concluder is implemented to give a conclusion as to whether or not to
admit the packet call depending on the amount of data measured at the queue processor.
5. A mobile packet communications system according to claim 1, comprising:
a buffer configured to store data addressed and transmitted to the currently set packet
calls;
a queue processor implemented to transfer onto the packet call the data stored in
the buffer;
a delay time calculator implemented to calculate a delay time depending on a time
when the data is stored in the buffer and a time when the data is transferred onto
the packet call by the queue processor, and
a delay time averager implemented to determine an average within a prescribed interval
with respect to the delay time calculated by the delay time calculator, wherein
the admission concluder is implemented to give a conclusion as to whether or not to
admit the packet call depending on the average determined by the delay time averager.
6. A mobile packet communications method comprising the steps of:
making, upon reception of a setup request of a packet call transmitted from a mobile
station, a decision depending on information on currently set packet calls stored
in a memory, as to whether or not the packet call setup-requested is a new call; and
concluding, upon a decision for the packet call to be the new call, whether or not
to admit the packet call.
7. A mobile packet communications method according to claim 6, wherein the concluding
comprises:
sampling a number of the currently set packet calls from the memory; and
giving a conclusion as to whether or not to admit the packet call depending on the
sampled number of the currently set packet calls.
8. A mobile packet communications method of a W-CDMA system implemented with a mobile
packet communications method according to claim 6, wherein the concluding comprises:
sampling a number of currently set A-DPCH's from the memory; and
giving a conclusion as to whether or not to admit the packet call depending on the
sampled number of the currently set A-DPCH's.
9. A mobile packet communications method according to claim 6, comprising the steps of:
storing in a buffer data addressed and transmitted to the currently set packet calls;
and
transferring onto the packet call the data stored in the buffer, measuring an amount
of data transferred onto the packet call per unit time, wherein
the concluding comprises giving a conclusion as to whether or not to admit the packet
call depending on the measured amount of data.
10. A mobile packet communications method according to claim 6, comprising the steps of:
storing in a buffer data addressed and transmitted to the currently set packet calls;
transferring onto the packet call the data stored in the buffer;
calculating a delay time depending on a time when the data is stored in the buffer
and a time when the data is transferred onto the packet call; and
determining an average within a prescribed interval with respect to the calculated
delay time, wherein
the concluding comprises giving a conclusion as to whether or not to admit the packet
call depending on the determined average.
11. A radio network controller for a mobile packet communications system comprising:
a memory configured to store information on currently set packet calls;
a new call decider implemented, upon reception of a setup request of a packet call
transmitted from a mobile station, to make a decision depending on the information
stored in the memory, as to whether or not the packet call setup-requested is a new
call; and
an admission concluder implemented, upon a decision for the packet call to be the
new call, to conclude whether or not to admit the packet call.
12. A radio network controller for a mobile packet communications system according to
claim 11, wherein
the memory is configured to store a number of the currently set packet calls, and
the admission concluder is implemented to sample the number of the currently set
packet calls, and to give a conclusion as to whether or not to admit the packet call
depending on the sampled number of the currently set packet calls.
13. A radio network controller for a mobile packet communications system of a W-CDMA system
configured with a radio network controller for a mobile packet communications system
according to claim 11, wherein
the memory is configured to store a number of currently set A-DPCH's, and
the admission concluder is implemented to sample the number of the currently set
A-DPCH's, and to give a conclusion as to whether or not to admit the packet call depending
on the sampled number of the currently set A-DPCH's.
14. A radio network controller for a mobile packet communications system according to
claim 11, comprising:
a buffer configured to store data addressed and transmitted to the currently set packet
calls; and
a queue processor implemented to transfer onto the packet call the data stored in
the buffer, measuring an amount of data transferred onto the packet call per unit
time, wherein
the admission concluder is implemented to give a conclusion as to whether or not to
admit the packet call depending on the amount of data measured at the queue processor.
15. A radio network controller for a mobile packet communications system according to
claim 11, comprising:
a buffer configured to store data addressed and transmitted to the currently set packet
calls;
a queue processor implemented to transfer onto the packet call the data stored in
the buffer;
a delay time calculator implemented to calculate a delay time depending on a time
when the data is stored in the buffer and a time when the data is transferred onto
the packet call by the queue processor, and
a delay time averager implemented to determine an average within a prescribed interval
with respect to the delay time calculated by the delay time calculator, wherein
the admission concluder is implemented to give a conclusion as to whether or not to
admit the packet call depending on the average determined by the delay time averager.